The present invention relates generally to construction materials and, more particularly, to the use of vegetable oil to create construction materials, such as building stone, stabilized soils, and improved soil-aggregate-bitumen mixes.
Modern society depends upon many environmentally hazardous products and processes. For example, the manufacture of modern construction materials may be destructive to natural habitats. Furthermore, construction materials are often manufactured from nonrenewable resources. However, environmental hazards exist beyond our dependency upon nonrenewable resources. Many of our most basic needs, such as food preparation, create environmentally hazardous byproducts. For example, under the Clean Water Act as amended by the Oil Pollution Act of 1990, disposal of vegetable oil carries many of the same risks to surface and ground water as petroleum. Despite the aforementioned problems, modern living requires the consumption of enormous quantities of both construction materials and vegetable oil.
Two of the most common materials used in construction and soil stabilization are bitumen and cement. Since about 3000 BC, bitumen mixtures have been used to seal cracks between stones in water reservoirs. For nearly as long, bitumen mixtures were used in the Middle East to pave roads. While bitumen can be found in nature, most bitumen is derived from petroleum. Asphalt, a common bitumen mixture generally used for paving, is composed primarily of hydrogen and carbon compounds and smaller quantities of nitrogen, sulfur, and oxygen. Furthermore aggregates, chemically inert particulate substances such as sand and gravel, are often added to asphalt. Bitumen in the form of asphalt emulsion is also sprayed over unsurfaced roads for dust control.
Concrete is a very common construction material. It is a mixture of aggregates, cement, and water. Cement is a finely ground powder that becomes solid when mixed with water through a process known as hydration. Hydration is the chemical combination of cement compounds and water to form submicroscopic crystals. Because of hydrating properties, constructional cements are often called hydraulic cements. Portland cement is a common hydraulic cement. Hydraulic cements are mixed with sand and water and used abundantly as injection grouts to stabilize underground soil formations and contaminated soil deposits.
Portland cement primarily consists of lime (CaO), silica (SiO2) and alumina (Al2O3). Each of these components must be quarried. After excavation, the quarried materials undergo four manufacturing stages: First, the raw materials are crushed. Second, the materials are blended. Third, the blended mixture is burned in a kiln from about 1,350xc2x0 to 1,550xc2x0 C. (2,460xc2x0 to 2,820xc2x0 F.). Lastly, the burned product is ground together with gypsum (to control the setting time of the cement).
Consequently, damage to the environment and energy expenditure involved in manufacturing both cement and asphalt is enormous.
Like asphalt and concrete, vegetable oil also endangers the environment. While the production of vegetable oil is not as environmentally destructive as the production of asphalt and concrete, the disposal of vegetable oil does present environmental problems. Because vegetable oil contaminates both ground and surface water, the EPA has included vegetable and other non-petroleum oils in Oil Pollution Act of 1990 amendment to the Clean Water Act. The hazards to the environment posed by vegetable oils include drowning waterfowl, killing fish, asphyxiating benthic life forms, and adversely affecting the aesthetic qualities of shorelines.
Because of the expense involved in disposing of used vegetable oil, industries producing waste vegetable oil have attempted to create uses for recycled vegetable oil. Currently, used vegetable oil can be added to animal feed, processed into lubricants, or manufactured into biodiesel. Despite these recycling efforts, according to the EPA (Report No. 530-R-97-015) in 1995, only five to ten percent of the total vegetable oil used was recycled.
Accordingly two needs exists. First, a need exists for construction and soil stabilization materials that are both less damaging to the environment and not dependent upon nonrenewable resources. Second, there exists a need to further exploit recycled vegetable oil.
In accordance with one embodiment to the present invention, a composition is provided. The composition includes a polymerized vegetable oil and a structural material. In certain embodiments of the present invention, the polymerized vegetable oil is substantially within a range of 2%-20%. In another embodiment, the composition includes a polymerized vegetable oil content that is substantially within a range of 3%-9% by weight of the structured material. In still yet another embodiment, the polymerized vegetable oil content is 5% by weight of the structural material.
In accordance with further aspects of this invention, the polymerized vegetable oil is a used vegetable oil. In yet other embodiments, the composition further includes a predetermined amount of a catalyst. In certain embodiments, the catalyst is a metallic catalyst. Other catalysts such as lime (CaO), flyash, and Portland cement are also within the scope of the present invention. In still yet other embodiments of the present invention, the polymerized vegetable oil is selected from a group that includes at least one of canola oil, soybean oil, sunflower oil, corn oil, rapeseed oil, palm oil, olive oil, and linseed oil.
In accordance with another embodiment of the present invention, a method for forming a structural composition includes mixing between 2% and 20% by weight polymerized vegetable oil with a structural material to create a composition. In one embodiment, a range of 3%-9% of polymerized vegetable oil is mixed with sand to create a composition. Certain embodiments also include heating the composition, compacting the composition, and curing the composition.